Caste certificate is earned or lost only by birth. There is no porcedure to change caste. If such procedure existed then many persons are craving to be declared as SC. They have to take the route of fraud only as no legal procedure is there. Such persons have the prosepects of going to jail.
You can cange relgiion but not the caste.
By the way if you intend not to use SC status then why apply SC certificate and why start a controversy inwhich you stand to gain nothing. You will achieve nothing except for losing the pride which you want to nuture. It is a matter of great dignity if one does not like to have a concessin legally available to him. Please do not deprive yourself of the same.